Fingerprint methods are common biometric measurements for user identification, and in recent years electronic fingerprint scanning has become commonplace. Even though contactless fingerprinting methods are used, it is more standard that the fingerprint is taken by pressing a finger against a computer scanner. Fingerprint image acquisition is considered the critical step of an automated fingerprint authentication system as it determines the fingerprint image quality, which has drastic effects on overall system performance where system performance is typically measured in terms of processing speed and accuracy. Concerning accuracy, “false positives”, where the system determines that there is a match when there is not a match, are the most damaging errors and are to be avoided as much as possible. In the past, the “wet ink technique” was used to obtain fingerprints. With that method, wet ink is applied to the fingertip which is then pressed against or rolled on a white card to obtain the best possible fingerprint image.
The market for biometric identification systems is driven largely by an increasing desire to free people from having to remember passwords. A system that positively identifies a person by any means that does not require memory of a password, physical possession of a key or magnetic card, or other fallible methods is needed for access to secure computing systems, access to secure physical spaces, banking, and other applications where accurate identification of a user is essential.
Presently on the market are various types of computer scanners used as fingerprint readers, but the method behind each type of scanner is to capture and store the fingerprint pattern with sufficient detail of the friction ridges and minutia since they are necessary for later comparison with other known prints. The process for capturing a fingerprint using a sensor consists of rolling or pressing a finger against the sensing area. The sensor itself can operate based on a variety of different principles, such as measurements of electrical resistance of a tested finger and imaging based on thermal or charge coupling devices. In any case, the whole print is needed and if the print taken is inadequate, the user must rescan until the system is able to determine the identity of that person.
The creation of finger decoys by groups of criminals and terrorists have recently prompted the development of blood vessel mapping technology which is expected to partially replace conventional fingerprinting technology. Finger vein scanners have been developed that map the blood vessels below the surface of a person's finger. Veins and other subcutaneous features present robust, stable and largely hidden patterns. An advantage of vein mapping systems is that the human vascular system is a unique and private feature of an individual. For example, identical twins have different and distinct infrared absorption patterns. Moreover, the vein patterns are not directly observed and therefore not easily replicated. The vein pattern will cease to exist only if a person's finger is cut off. Nonetheless, questions still remain as to whether a person's vascular pattern may be subject to change due to medical conditions, level of personal smoking, or based on a simple factor such as hand temperature. Consequently, the use of vein mapping in isolation is problematic.
Security of personal information is currently gaining greater importance. In fact, biometrics authentication technology is attracting attention as a way to ensure security of individuals. Biometrics authentication is authentication technology that uses biological information of a person, and is excellent in terms of convenience and preservation of confidentiality. Examples of known conventional biometrics authentication technology include authentication using a fingerprint, iris, voice, face, or vein on the back of a hand or on the palm side of a finger. In particular, vein biometric authentication is highly fraud-proof in terms of use of in vivo information.
A number of companies are currently manufacturing and marketing fingerprint-based personal identification devices. These products identify a person by reading his or her fingerprint by having the fingerprint come into contact with a fingerprint sensor, recognizing end points and branching points of the fingerprint, and collating them with characteristic points of registered fingerprints. These techniques typically use an image of the fingerprint that may be abstracted into some representation of the fingerprint that is then matched against known fingerprints. Therefore intercepting the fingerprint is an effective way to defeat these systems. Consequently, a second factor can be added to increase reliability.
The easiest two-factor system adds a personal identification number (PIN) or password to the fingerprint scan. This is not a one-touch two-factor technique but it can be effective in ensuring that the person belonging to the fingerprint also knows the PIN. It has two key drawbacks. First, it does not remove the need to remember a password, and second, if the password can be obtained and the fingerprint intercepted, the system can still be defeated.
One current one touch two-factor method and system for characterizing a person uses light imaging devices to take a surface image of at least one fingerprint of a user's finger and the vein map below the surface of the user's finger. Once these images have been taken, they are normally stored in a database for later comparison and verification of the user. Notably, the stored images of a fingerprint can pose serious problems for a user. For instance, the stored fingerprint images of a finger can be replicated or reverse engineered by criminals or terrorists for illegal purposes. A breach of a fingerprint database is far worse than a breach of a password file. Passwords can be changed but fingerprints cannot. Therefore, there is a requirement to avoid any possibility of intercepting fingerprints that could be used maliciously.
A further problem posed by current methods and systems for capturing the image of a user's fingerprint is related to the amount of data that has to be captured. Current methods and systems generally have to capture almost the entire surface area of a user's finger for the information to be useful for later comparison and verification of a person. This leads to errors such as false negatives when verifying a person's fingerprint since so much data has to be compared. This is more of an inconvenience than a security problem because the remedy is to rescan the fingerprint, but as stated earlier, when the fingerprint itself is stored for later comparison, this is where the security problem lies.
United States Patent Application Publication No. 2007/0177767 describes a user-friendly compact system that is used for capturing a vein pattern in a finger. The method involves contact of the finger with the surface. The method operates in reflection mode, where the emitter and detector are on the same side. U.S. Pat. No. 5,751,835 describes capturing capillaries in a fingernail using fibers. The method involves contact of the object with a surface and works in reflection mode. United States Patent Application Publication No. 2007/0058841A1 describes a system embedded in a doorknob that captures vein images in finger. The system works in the transmission mode but the camera is on the opposite side from the palm side of the hand. The method involves contact with the surface.
United States Patent Application Publication No. 2005/0047632A1 acquires a vein pattern in the finger using a transmission mode of operation. U.S. Pat. No. 7,266,223 B2 describes vein pattern acquisition in transmission mode with positioning of the finger being partially by contact and partially without contact. United States Patent Application Publication No. 2011/0007951 describes a system and method for identification of fingerprints and mapping of blood vessels in a finger. The system and method both require a light-imaging device that takes images of the surface and subsurface of a user's finger that has to be rotatable about at least one axis.
Accordingly, there exists a need for physiologically identifying a person by means of a one touch two factor biometric method and system for increasing and ensuring security of individuals that utilizes a portion of a user's fingerprint and the vein map below the surface of the user's finger.